Research on PWM techniques of five-phase three-level inverter

Aiming at five-phase permanent magnetism synchronous motor (PMSM), this paper sets up the variable-frequency variable-speed system supplied with three-level inverter and makes study about PWM control algorithm of five-phase three-level inverter. In multilevel inverter, Switching Frequency Optimal PWM(SFOPWM) has many advantages such as high voltage usage and simple control, but the calculation of zero-sequence component in the five-phase three-level inverter need to be studied. This paper propose a calculation method of zero-sequence component in five-phase inverter, which is proved in SFOPWM. For multi-phase multi-level inverter, the numbers of voltage vector and switching state grow rapidly with the increment of phase and level. On the basis of profound analysis about characteristic and rule of five-phase three-level inverter's voltage vector, a simple and practical control algorithm of voltage space vector PWM(SVPWM) is put forward, and it is proved by simulation experiment.